Open Access

Table 2

Data of the homogenized series of the annual number of prominences with heights of 25 and more of the Madrid Astronomical Observatory obtained in this work for the period 1906–1957. The columns represent: (i) the year of the observations, (ii) the number of observation days in the corresponding year, (iii) the number of prominences observed in the corresponding year, and frequency of the (iv) total, (v) north, and (vi) south number of prominences (that is, the total, north, and south number of prominences divided by the number of observation days).

Year Days N ft fn fs Year Days N ft fn fs
1906 152 635 4.18 2.45 1.72 1934 85 297 3.49 1.61 1.88
1907 138 742 5.38 2.74 2.64 1935 256 1243 4.86 2.20 2.68
1908 194 1090 5.62 2.50 3.12 1936 169 1097 6.49 3.37 3.22
1909 218 1028 4.72 2.37 2.35 1937 184 1178 6.40 3.13 3.27
1910 200 697 3.48 1.56 1.92 1938 100 347 3.47 2.20 1.39
1911 156 248 1.59 0.47 1.12 1939 40 186 4.65 2.76 1.91
1912 174 353 2.03 0.60 1.43 1940 54 259 4.80 2.09 2.70
1913 153 382 2.50 0.97 1.53 1941 102 347 3.40 1.91 1.49
1914 163 501 3.07 1.31 1.77
1915 114 756 6.63 3.35 3.28 1943 24 81 3.37 1.13 2.25
1916 146 1254 8.59 4.57 4.02 1944 184 580 3.15 1.53 1.62
1917 113 1115 9.96 5.28 4.68 1945 147 711 4.84 2.14 2.70
1918 117 882 7.54 4.00 3.54 1946 98 724 7.39 3.67 3.81
1919 137 838 6.12 3.43 2.69 1947 94 756 8.04 4.30 4.00
1920 107 565 5.28 2.36 2.92 1948 122 1020 8.36 4.11 4.68
1949 130 967 7.44 4.40 3.35
1925 62 462 7.45 4.50 2.95 1950 115 609 5.3 3.0 2.4
1926 88 674 7.86 4.49 3.37 1951 163 762 4.7 2.3 2.5
1927 106 715 6.75 3.70 3.05 1952 155 540 3.5 1.9 1.7
1928 102 716 7.02 3.36 3.66 1953 204 561 2.8 1.4 1.3
1929 74 364 4.92 1.90 3.02 1954 257 593 2.3 1.3 1.0
1930 122 445 3.65 1.88 1.77 1955 177 616 3.5 2.1 1.4
1931 143 502 3.51 1.78 1.73 1956 221 925 4.2 2.4 1.8
1932 153 451 2.95 1.76 1.19 1957 34 124 3.6 2.1 1.5
1933 136 370 2.72 1.66 1.06

Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.

Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.

Initial download of the metrics may take a while.